The employer has more resources than the employee. Lawyers and private investigators would be a start. If I ran a company and found out my customers were sendin

The employer has more resources than the employee. Lawyers and private investigators would be a start. If I ran a company and found out my customers were sending death threats to my staff, I wouldn't care where it occurred and would throw a good amount of resources at finding out who they were, having them prosecuted, and then publicising the results as a sort of modern version of putting heads on spikes. edit - though I would go to the person making the threats and give them the opportunity to make amends first before involving any level of publicity or authority.